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From:   Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Date:   Tue, 22 Mar 2022 21:47:56 +0700
Message-ID: <CAOG64qP=Hn+Z6zO2pEafE4acLiGig79OCPQCAktb4bhV6DFBAg@mail.gmail.com>
Subject: Re: [RFC PATCH v2 3/8] tools/nolibc: i386: Implement syscall with 6 arguments
To:     David Laight <David.Laight@aculab.com>
Cc:     Willy Tarreau <w@1wt.eu>, Ammar Faizi <ammarfaizi2@gnuweeb.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Nugraha <richiisei@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "GNU/Weeb Mailing List" <gwml@vger.gnuweeb.org>,
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On Tue, Mar 22, 2022 at 8:37 PM David Laight wrote:
> dunno, 'asm' register variables are rather more horrid and
> should probably only be used (for asm statements) when there aren't
> suitable register constraints.
>
> (I'm sure there is a comment about that in the gcc docs.)

I don't find the comment that says so here:
https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html

The current code looks valid to me, but I would still prefer to use
the explicit register constraints instead of always using "r"(var) if
available. No strong reason in denying that, tho. Still looks good.

-- Viro